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中庭烟气管理系统的设计导则回顾 总被引:2,自引:0,他引:2
本文回顾在中庭中常用的烟气管理设计导则。概括了在这些导则中采用的不同方法,并解释了这些方法背后的烟气物理。这些设计导则中的烟气动力学的工程原理是相似的。基本上,方法包括强加逆向流来阻止烟气蔓延,采用压差来对付物理障碍物,烟气稀释和抽取。烟气通风看来是中庭中烟气管理的常用方法,可以将烟气层界面的高度保持在可接受值,或者至少降低烟气层的下降速率。这些导别给出了设计的一般原则,但并未覆盖所有中庭,特别是在远东地区新建建设性项目中的中庭。 相似文献
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为了探讨生物质燃烧过程中正构烷烃化学组成及其碳同位素的变化规律,对4种玉米秸秆进行了室内焚烧实验,用GC-MS和GC/C/IRMS方法对燃烧前后的样品进行测定.结果表明,秸秆中正构烷烃的碳数为C13~C35,分布形态为单峰型,主峰碳数为C31.正构烷烃的碳优势指数(CPI)值为1.1~5.3,平均碳链长度(ACL)为25.1~28.8.明火烟尘中正构烷烃的碳数为C14~C35,呈双峰型分布,2个主峰碳数分别是C18和C31.其CPI值为1.0~2.4,ACL值为23.0~26.8.正构烷烃单体碳同位素比值为-20.1‰~-33.5‰.闷烧烟尘中正构烷烃的碳数是C12~C35,CPI值为2.2~4.8,ACL值为26.6~28.9.其含量呈双峰式分布,2个主峰碳数分别是C22/C23、C31.正构烷烃单体碳同位素比值为-21.5‰~-32.5‰.在明火烟尘和闷烧烟尘中,正构烷烃的单体碳同位素组成与原秸秆中同碳数正构烷烃的差值分别为-13.8‰~5.4‰、-6.7‰~ -5.1‰.2种烟尘中正构烷烃的化学组成与碳同位素分布都与原玉米秸秆有着显著的差别. 相似文献
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Yusi Liu Xingru Li Guiqian Tang Lili Wang Bo Lv Xueqing Guo Yuesi Wang 《环境科学学报(英文版)》2019,31(6):107-115
Secondary organic aerosols(SOAs) are an important component of particulates, but whether biogenic SOAs(BSOAs) or anthropogenic SOAs(ASOAs) are the dominant contributors to haze pollution remains poorly characterized. In this study, particulate samples were collected from September 2014 to August 2015 at an urban site in Jinan, which is the capital of Shandong Province and a typical city in the North China Plain. The PM2.5 samples were analyzed for BSOA(isoprene(SOAI) and monoterpenes(SOAM)) and ASOA(aromatic(SOAA)) tracers. The concentrations of the SOAAtracer(1.1 ± 1.0 ng/m3) were lowest, and those of SOAItracers(41.8 ± 86.2 ng/m3) were highest, with the concentrations of SOAMtracers(19.4 ± 9.9 ng/m3) being intermediate. The SOAItracers were more abundant in the summer and less abundant in the winter. Both SOAIand SOAMincreased with increasing ozone level but decreased with increasing NOx level. Correlation analysis revealed a good correlation between 2,3-dihydroxy-4-oxopentanoic acid and levoglucosan levels in three seasons. These results suggested that biomass burning activities occurring in the NCP can enhance the emissions of aromatics and should be controlled, especially in the autumn and winter. SOA tracers were classified according to pollution degree, and the results showed that as pollution increases, the contributions of SOAAincrease. These results indicate that reducing anthropogenic emissions is necessary to prevent SOA pollution, especially during heavy pollution episodes. 相似文献
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Jukka Miettinen Soo Chin Liew 《Mitigation and Adaptation Strategies for Global Change》2009,14(4):357-373
In this study we used high resolution (20 m) land cover maps to derive detailed information on land cover structure within
the classes of a regional medium resolution (500 m) land cover map. This enabled improved biomass estimation for the medium
resolution land cover classes. Although our results suggested that land cover maps based merely on medium resolution remote
sensing data can be used to monitor the extent of forest cover, they also showed that these maps alone are not sufficient
to produce reliable regional estimates on above ground biomass in insular Southeast Asia. A quarter of the study area was
covered by sub-pixel size (500 m) mosaic of various land cover types containing 14% of biomass. In total, non-forest areas
covered over 60% of the study area and included 43% of biomass. In these areas, highly fragmented within class land cover
structure was shown to significantly affect biomass estimates. Therefore we conclude that forest/land cover monitoring based
merely on medium resolution remote sensing data can no longer be used to sufficiently quantify carbon fluxes connected to
land cover changes in insular Southeast Asia, but multi-resolution approaches are needed to perform this task. 相似文献
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提出在加强对餐饮业环境管理的同时,务必注意油烟监测中的技术问题。指出油烟测试中,不锈钢滤筒优于刚玉滤筒;应用红外分光法测定油烟含量,不受油品成分限制,结果较准确、可比。由于厨房的实际工作灶头数不同,每个灶头发热功率的不同和每个灶头产生油烟量的不同,必须把实际工作灶头数换算为折算工作灶头数,才具有一致性和可比性。折算工作灶头数n=(工作灶头数/实际灶头数)×(排风罩面积/1.1)。 相似文献